"The worms? It sounds like _hundreds of them_! We better work fast, or they'll have the whole roof down around our ears." "No, John. We can't fight them with guns. _They have attacked every dome on the planet!_" When full realization came to the big Irishman, he sank slowly into a chair. "Then what? Have you got any plan--or are we helpless?" "We've got work to do and plenty of it. There's a slight chance of saving the cities. I've already instructed the others." As the three men raced toward the power plant, Dick explained. John and George were to do the work, while he traveled from dome to dome to make sure the people were prepared, and see that the power plants were used as he intended. By the time they reached the entrance of the building, John nodded, and Barrow turned back as the other men entered the door. The first dome people that Dick saw were told to remove everyone from the buildings, and gather them in the open spaces of the parks. _Leaving no one within any structure!_ The expression on his face scared them even more than the pounding of the worms, and they hurried to obey. Dick jumped into the nearest ground car. He couldn't be bothered traveling on the railroads. This happened to belong to the assistant head of the dome, whom he dispossessed. It jerked crazily across streets and parks, while he learned to handle the controls. An hour later Dick was back at the powerhouse in the big dome. Every city was ready. In several places the hammering heads had broken through the outer layers, and were banging at the translucent inner ceiling. The creatures _had learned how_ to break through. The first worm that attacked, while the space ship was away, either took its time or didn't realize what was beneath the heavy metal. These creatures were working in earnest. Heavy insulated cables ran from the powerhouse to the nearest metal pillars, where McCarthy and Martin were working desperately to fasten them in place. The booming voice of the Irishman had kept the natives back, although they crowded as close as they dared. They were really afraid, when the hammering grew plainer with each passing minute. When the cables were fastened, John shouted to Dick, who was waiting in the powerhouse. He pulled a heavy switch, at the end of the wires. The city was suddenly in complete darkness, then it flashed bright again as power flowed back into the thousands of coils in the ceiling material. Twice more it darkened, when the giant switch was thrown, and the lights came on again. This time it stayed bright. Dick ran to the doorway, and gazed at the dome above. _It was silent!_ The people were frightened, and moved restlessly about. Twice more he turned the power into the metal, and after one long darkened period, the city remained bright. _No sound came from the dome!_ Either the worms were dead--or frightened away!